Due to the recent explosive growth of high-definition content, a demand for more efficient use of a video streaming service and network is raised. Accordingly, in order to create a standard for adaptive streaming that uses HTTP, Dynamic Adaptive Streaming over HTTP (DASH) was developed in the Moving Picture Experts Group (MPEG) forum.
DASH is a technology that initially breaks up a content into segments, each segment having a certain bitrate, for which their corresponding representations each have different durations; and then, during streaming, transmits the segments encoded based on their respective bitrates, according to the network's measured bandwidth.
However, once the transmission of the selected segment has begun, even if there is a change in network bandwidth, another segment, which has been encoded at the bitrate that corresponds to the changed bandwidth, cannot be selected and transmitted. Only when a new representation begins, one of the segments, encoded at various bitrate and which is of said new representation can be selected and transmitted.
Furthermore, if the duration of the representation is long and the network environment thereof is one in which the bandwidth changes rapidly, content streaming that is adaptive to the bandwidth is difficult; however, if the duration of the representation is short and the network environment thereof is one in which the bandwidth changes slowly, an overhead is incurred due to the additional representation that is generated.